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B Dahl

Publications and source records attributed to B Dahl.

At least 37 records · Page 2Linked to original sources
PubMed1995

Functional and social long-term results after free tissue transfer to the lower extremity.

We report the long-term social and functional results in 53 patients receiving free tissue transfer after trauma to the lower extremity. The results are compared with those of a matched group of patients receiving primary amputation. The microsurgically treated patients had significantly more complaints over pain during walk (p = 0.02) and edema (p < 0.00005). Regarding social results, no significant differences between the two groups were found. Time until surgery, infection, or bone defect before free flap surgery did not alter the overall results significantly. It is concluded that the long-term functional and social results after free tissue transfer are almost the same as those achieved after simple amputation. Because the median time until free flap surgery in this series was 158 days, early limb-saving procedures could possibly improve the long-term results.

Adult↗
PubMed1993

The relationship between inert gas wash-out and radioactive tracer microspheres in measurement of bone blood flow: effect of decreased arterial supply and venous congestion on bone blood flow in an animal model.

Several methods have been employed in the study of bone perfusion. We used a method of determining inert gas wash-out by mass spectrometry in the study of blood flow rates in pigs. The method was validated by comparison of the result obtained with inert gas wash-out to that with measurement by microspheres. Furthermore, the effect of decreased inlet flow and venous congestion on the bone perfusion data was tested. The undisturbed bone blood flow was not significantly different when measured with wash-out of inert gas (7 +/- 0.7 ml/min/100 g) or with microspheres (9 +/- 2.9 ml/min/100 g), and the methods were correlated. Perfusion was reduced significantly, to 20% of the original value, after arterial occlusion. The changes in wash-out curves and accumulation of radioactive tracer provided substantial evidence for impaired intraosseous circulation following venous obstruction also. In conclusion, the study showed that this method of determining inert gas wash-out is feasible for studies of local perfusion rates in bone. The flow rates obtained by wash-out correlated well with the results of microsphere studies. In this animal model, both methods detected a fivefold reduction in flow rate after clamping of the arterial inflow. Obstruction of the venous outflow also impaired blood flow and lowered the cellular supply.

Animals↗
PubMed1993

Laser Doppler flowmetry for estimation of bone blood flow: studies of reproducibility and correlation with microsphere technique.

The blood flow in the femoral condyles of six pigs was measured by the microsphere technique and by laser Doppler flowmetry (LDF) before and after clamping of the external iliac artery. A significant decrease in the bone blood flow was found with both microsphere and LDF measurements, and a high correlation was found between the two methods. After release of the arterial clamp, the LDF values rapidly returned to approximately the same values as before clamping. In a second part of the study, the LDF output signal was studied in the intertrochanteric area of eight patients. The reproducibility of two LDF measurements at the same location was within 15%. The temporal variability of the LDF signal during 10 min of recording showed only slight variations. It is concluded that LDF is relative in nature and that the mean LDF output signal is suitable for monitoring dynamic responses of the bone blood flow to various stimuli. Several consecutive measurements have to be performed if the blood flow at different locations of a specific bone are to be compared with each other.

Animals↗
PubMed1992

[Oxygen conserving nasal catheters. Oxymizer pendant].

The Oxymizer pendant consists of a 40 ml pendulating reservoir bag which is connected to the prongs by two tubes. Both reservoir and tubes serve as oxygen reservoirs. We wanted to examine if it was possible to save oxygen by changing from the usual nasal cannula to Oxymizer pendant. 11 patients with hypoxaemia due to chronic obstructive pulmonary disease were examined. We were able to reduce the oxygen requirement by approximately 65% without significant changes in SaO2. All 11 patients evaluated the Oxymizer pendant to be more comfortable than the usual nasal cannula.

Catheterization↗
PubMed1992

Partial pressures of oxygen and carbon dioxide in bone and their correlation with bone-blood flow: effect of decreased arterial supply and venous congestion on intraosseous oxygen and carbon dioxide in an animal model.

Pathological changes in bone have been related to a preceding impediment of the arterial or venous bone circulation and hypoxia. In this study, we analyzed the feasibility of mass spectrometry in measuring intraosseous oxygen and carbon dioxide. The partial pressures were also measured in intraosseous blood samples, and blood flow in bone was measured with the radioactive microspheres technique. The average partial pressure of oxygen in the lateral femoral condyle was 34 +/- 1.6 mm Hg when measured in intraosseous blood samples and 36.3 +/- 2.3 mm Hg when measured with the on-line mass spectrometer, with significant correlation between the methods. The absolute value of the partial pressure of carbon dioxide measured in situ with mass spectrometry was correlated with the value in the withdrawn blood. There was no significant difference in partial pressures of oxygen and carbon dioxide between the two sides or between repetitive measurements. Arterial occlusion resulted in severe hypoxia, whereas more moderate changes followed venous occlusion.

Animals↗
PubMed1991

Older's classification of Colles' fractures. Good intraobserver and interobserver reproducibility in 185 cases.

To evaluate the reliability of the Older classification, 4 observers classified 185 distal radius fractures twice with 1 month's interval. Both the intraobserver agreement and the interobserver agreement were high, with kappa values of 0.75 (0.69-0.79) and 0.69 (0.60-0.77), respectively. The agreement was especially high for type 1 and type 4 fractures. Older's method of classifying distal radius fractures can thus be recommended for clinical use.

Colles' Fracture↗
PubMed1990

Characterization of rat brain NCAM mRNA using DNA oligonucleotide probes.

A number of different isoforms of the neural cell adhesion molecule (NCAM) have been identified. The difference between these is due to alternative splicing of a single NCAM gene. In rat brain NCAM mRNAs with sizes of 7.4, 6.7, 5.2, 4.3 and 2.9 kb have been reported. We have synthesized six DNA oligonucleotides, that hybridize to different exons in the NCAM gene. Furthermore we have constructed three oligonucleotides, that exclusively hybridize to mRNAs lacking certain exons, by letting them consist of sequences adjacent to both sides of the splice sites. By means of these probes we have characterized the five NCAM mRNAs in rat brain.

Animals↗
PubMed1990

The possible use of a spallation neutron source for neutron capture therapy with epithermal neutrons.

Spallation is induced in a heavy material by 72-MeV protons. The resulting neutrons can be characterized by an evaporation spectrum with a peak energy of less than 2 MeV. The neutrons are moderated in two steps: first in iron and then in carbon. Results from neutron fluence measurements in a perspex phantom placed close to the moderator are presented. Monte Carlo calculations of neutron fluence in a water phantom are also presented under some chosen configurations of spallation source and moderator. The calculations and measurements are in good agreement and show that, for proton currents of less than 0.5 mA, useful thermal-neutron fluences are attainable in the depth of the brain. However, the dose contribution from the unavoidable gamma background component has not been included in the present investigation.

Boron↗
PubMed1990

Blood oxygen parameters in patients with chronic obstructive pulmonary disease. An evaluation of measured and calculated 2,3-diphosphoglycerate concentrations.

48 simultaneous arterial and venous blood samples from 15 patients with chronic obstructive pulmonary disease (COPD) were evaluated for calculated p50 and measured and calculated 2,3-diphosphoglycerate (DPG) concentration. 23 samples (48%) demonstrated a leftward shift in the calculated in vivo p50, whereas both measured and calculated DPG showed 5% below and 28% above reference range. Measured DPG was significantly higher than calculated DPG in the leftshifted group, whereas there was no significant difference in the non-leftshifted group. Mean arterial pH was alkalotic in the leftshifted group and significantly higher than mean pH in the non-leftshifted group. It is concluded that DPG concentration cannot be calculated by the algorithm in patients with COPD and a leftward shift in the oxygen dissociation curve.

2,3-Diphosphoglycerate↗
PubMed1990

Health problems in Norwegians travelling to distant countries.

373 travellers to countries outside Europe and North America were recruited before departure summer 1988 at the Vaccination Office, Trondheim, Norway, and participated in a follow-up study on health problems related to travel. 313 of the travellers (84%) responded by answering a postal questionnaire one month after return; it dealt with prophylactic measures, life-style, and health problems associated with travelling. An 18% failure in malaria prophylaxis and some risk-taking behaviour related to alcohol and sex were recorded. Diarrhoea (usually mild) was reported by 59%; other symptoms were also frequent. Medical advice was sought by 18% while abroad; 7% consulted a doctor. Ill health made travelling less enjoyable than expected for 8%. After return, 25% had health problems; 9% saw a doctor, three travellers were hospitalized, and 6% were absent from work. Total morbidity was high, but seldom serious. Targeted advice, which can well be given by primary health care personnel, could help to reduce morbidity and risk behaviour and improve travellers' handling of ill health.

Adolescent↗
PubMed1989

Pars plana vitrectomy and silicone oil injection in proliferative diabetic retinopathy.

A retrospective study is reported on 106 eyes with proliferative diabetic retinopathy, treated by vitrectomy and silicone oil injection. Indications were traction detachment in 91 eyes and nonclearing rebleeding in 15 eyes; 31 eyes had previously had vitrectomy. Anatomical success was obtained at the end surgery in 91 eyes, and after a minimum follow-up of 6 months in 68 eyes (64%). Functional results were as follows: satisfactory visual acuity (0.5-0.05) in 23 eyes (22%), ambulatory vision (0.03-CF) in 14 eyes (13%), HM-LP in 54 eyes (51%), and NLP in 15 eyes (14%). The functional results are limited by recurrent detachments due to characteristic reproliferations under the silicone bubble or by ischemic diabetic angiopathy in the attached retina. A positive effect of silicone oil is demonstrated in the reduction of preexisting or postoperatively new iris neovascularization and in preventing postoperative rebleeding.

Adult↗
PubMed1989

The production by 72 MeV protons of keV neutrons for 10B neutron capture therapy.

Fast neutrons, produced in a spallation process by 72 MeV protons hitting heavy nuclei, can be moderated down to keV energies, suitable for 10B capture therapy. Measurements of neutron flux from copper and lead targets, after moderation by water and hydrocarbons, have been performed, together with measurements of the fast neutron and gamma-backgrounds. The comparisons with Monte Carlo calculations show good agreement. As neutron fluences up to 10(12) to 10(13)n/cm2 can be produced within a few hours in about 0.5 m target distance the technique seems to be suitable for clinical experiments.

Boron↗
PubMed1988

Inoculation with BK virus may break immunological tolerance to histone and DNA antigens.

BK virus particles contain histones of host cell origin that combine with viral DNA to form minichromosomes. Data from earlier immunoblotting experiments demonstrated that rabbits inoculated i.v. with purified infectious BK virus produced antibodies not only to the viral structural protein VP1 but also to migrating polypeptides of a molecular mass ranging from 14-16 kDa. These proteins were believed to represent certain histone classes. To examine this hypothesis, sera from five rabbits inoculated with BK virus were analyzed by ELISA for antibodies against polynucleosomes, the individual histone classes, and double-stranded DNA, as well as against antigens carried by the structural viral proteins. Antibodies against polynucleosomes and also against histones H1 and H3 were found in sera from two of five inoculated rabbits. The same sera contained antibodies reacting with double-stranded DNA, whereas no antibodies against H2A, H2B, and H4 were detected. BK virus inoculation may thus lead to a break of tolerance, resulting in autoantibody production against highly conserved antigens that, in this context, may be regarded as "self-antigens", irrespective of the species in which they originate.

Animals↗
PubMed1977

Treatment of psoriasis vulgaris with a new retinoic acid derivative Ro 10-9359; An uncontrolled clinical trial.

The retinoic acid derivative Ro 10-9359, given orally in maximum daily doses of 100 mg to 15 patients with psoriasis vulgaris, led to clearing of the lesions in 8 patients. The average period of treatment was 9 weeks. In 14 patients side-effects were observed, the most important being palmo-plantar desquamation, shivering, thirst and diffuse hair loss. In 2 patients scaling led to withdrawal. In 6 patients abnormal alkaline phosphatase and glutamic-aspartatic transaminase values, partly transient, developed (glutamicaspartatic transaminase, p less than 0.01).

Alkaline Phosphatase↗